A note of CAUTION.....
Caution
We would like to share our experience in finishing the curved angle iron.
Having made a carefull copy of the curve on a thick Oak plank and carefully cut out segments which were tacked welded using a Mig welder we continually compared our new angle iron against a salvaged angle iron to insure exactly the curve and fit. The original angle iron had been confirmed accurate by comparing it to the floor of my cab 11.
So completely assured that we had the correct curve I proceeded with the permanent welding of the 12 cuts. We staggered the welds to prevent distortion and finished by carefull grinding on both side. We set the heat to fairly high to insure proper penetration of the weld and to keep the rise of the weld bead to a minimum.
When we stacked up the new angle against the old one we were off by at least 12mm or 1/2 inch. THE SUCCESSION OF HIGH HEAT WELD ACTUALLY SHRANK THE CURVE 12MM OR 1/2 IN. TIGHTER
Not to despair. We carefully hammered the inside flat of the angle iron, to stretch the metal this time, until we had a perfect copy of the old original piece. It does take a fair amount of heavy hammering but eventually, we compared the gradual changes repeatedly against the wooden form and the original piece.
We are also fortunate that our work table, which was salvaged from a Lumonix Laser research centre is built with a 5/8 thick Stainless Steel top mounted on massive square tubing legs with casters. It weight about 1600 pounds and is a beautiful anvil and very flat set up table/welding table.
If we had to do another one we would hammer our welds after each one is done while still semi hot and also to reduce the grinding and keep the shrinkage in check.
Next weekend we will be removing/cutting out the rusted angle now bolted in the jig and bolt the new angle on place for welding the left and right hand section together. The jig weights more than the back wall itself but will insure an accurate alignment of the new angle iron base plate for the wall.
Amazing what you can do with some patience.
Cheers
__________________
Bob Carriere....B.T.B
C15a Cab 11
Hammond, Ontario
Canada
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